The TARDIS (Time and Relative Dimension in Space) is a time machine and spacecraft in the British science fiction television program Doctor Who and its associated spin-offs. A TARDIS is a product of the advanced technology of the Time Lords, an extraterrestrial civilization to which the programme's central character, the Doctor, belongs. A properly maintained and piloted TARDIS can transport its occupants to any point in time and any place in the universe. The interior of a TARDIS is much larger than its exterior, which can blend in with its surroundings using the ship's 'chameleon circuit'. In the series, the Doctor pilots an unreliable, obsolete TT Type 40, Mark 3 TARDIS.
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